Dustin Ackley homered in his second big-league game, furthering the notion that he is in Seattle to stay. At the ever-thin fantasy position of second base, Ackley could be a revelation for those lucky enough to have him on their squads, both for this season as well as for years to come in keeper circles.

Who's next in line for greatness? Let's look in this week's Minor League Barometer.

UPGRADE

1. Jedd Gyorko, 3B, SD - Gyorko's last 10 games haven't been too shabby. Over that span, the 22-year-old is batting .442/.500/.605 with one home run, five RBI and one stolen base at High-A Lake Elsinore. The scary part for Gyorko? His overall line for the Storm is not that far off, as he is hitting .381/.444/.650 with 15 home runs, 67 RBI and 11 steals. Though he likely won't receive a promotion until James Darnell gets one at Double-A, both third basemen are surging and could see the next level of competition shortly.
2. Devin Mesoraco, C, CIN - Here's your dilemma if you're Cincinnati, and it's a good one to have. The Reds are fighting for a playoff spot with two serviceable catchers in Ramon Hernandez and Ryan Hanigan. Nevertheless, Mesoraco is having his way with Triple-A pitching with an overall line of .323/.404/.547 with eight home runs and 42 RBI for the Bats. The Reds have a similar problem with Yonder Alonso; however, nobody is suggesting he replace Joey Votto at first, and his forays into the outfield have been met with mixed reviews. Obviously, Hernandez and Hanigan are not in Votto's class, but they have still been effective for the Reds. First-round pick Yasmani Grandal is also surging up the ranks at the catching position, currently at High-A. The solution? Not easily discernible, but Mesoraco should come up as a September call-up at the very least, with an eye toward competing for the starting catching position in 2012.
3. Randall Delgado, P, ATL - Delgado made his big-league debut with a spot-start for the Braves last week when Tommy Hanson was placed on the 15-day DL. While he wasn't exactly dominant (seven hits and three earned runs in 4.0 innings against the Rangers), he showed some promising signs, including a 1.75 GO:AO ratio. Likewise, it speaks volumes to his future potential that the Braves were willing to call him up straight from Double-A Mississippi. Though Delgado was subsequently demoted and will likely continue to pitch at Double-A Mississippi for now, his promise remains bright for Atlanta, where he and Julio Teheran are merely caught in a numbers game at this point.
4. Michael Choice, OF, OAK - A's hitting prospects have received a bad rap the last year or two, so let's highlight something positive. Over his last 10 games, the No. 10 overall selection in the 2010 draft is batting .300/.391/.750 with five home runs, 10 RBI and even a stolen base for High-A Stockton. The 21-year-old outfielder has pushed his overall stats to .248/.350/.504 with 16 home runs, 44 RBI and seven steals for the Ports. Although much like bopper Chris Carter in that he continues to strike out too much (82 Ks in 65 contests), Choice has raw power with the ability to draw walks, making him an attractive phenom for the offensively-challenged Athletics.
5. Trayvon Robinson, OF, LAD - Check out Robinson's last 10 contests; the 23-year-old outfielder is hitting a robust .531/.625/.844 with two home runs and 10 RBI for Triple-A Albuquerque. Overall, he is batting .314/.380/.567 with 15 home runs, 44 RBI and seven steals for the Isotopes. With Tony Gwynn Jr., Trent Oeltjen and Marcus Thames hitting less than .220, and Jerry Sands already back in Triple-A, Robinson's time for a promotion could be approaching rapidly.
6. Tom Milone, P, WAS - A 10th-round pick in the 2008 draft, Milone was the Nats' Minor League Pitcher of the Year in 2010, posting a 2.85 ERA and 155:23 K:BB ratio through 158.0 innings at Double-A Harrisburg. His control has been pristine as well in 2011 for Triple-A Syracuse, as the 24-year-old lefty has accumulated an astounding 82:5 K:BB ratio this season. Milone is not talked about because of a fastball that only peaks at about 90 mph, but he has a stellar changeup, knows how to pitch and has excelled at every level in the minors. The polished left-hander could see the big leagues before 2011 is finished.
Honorable Mention

1. Lonnie Chisenhall, 3B, CLE - A combination of factors has led to Chisenhall still toiling in the minors this season, and now he has landed on the DL due to lingering concussion issues. Before the injury, Chisenhall was having only an average 2011 campaign for Triple-A Columbus, hitting .250/.344/.392 with five home runs and 30 RBI through 60 games. With the Indians still in the hunt for supremacy in the AL Central, Jack Hannahan has adequately handled third base for the Tribe, allowing them to give Chisenhall more time to refine his skills in the minors. Likewise, the concussion certainly dampers hopes of a 2011 promotion, as we've seen worst-case scenarios like Justin Morneau missing significant time with head injuries. Suffice to say, Chisenhall looks like a September call-up at best at this point.
2. Lars Anderson, 1B, BOS - Anderson has to fight a double whammy; not only is he struggling at the plate, but he is also stuck behind Adrian Gonzalez and David Ortiz. Over his last 10 games for Triple-A Pawtucket, Anderson is batting just .125/.205/.200. Overall, the 23-year-old's power has been severely lacking, as Anderson has smacked just four home runs through 65 games. Though his eye remains stellar at the dish, his plate discipline appears to be his only plus-tool at this point. However, Anderson has also fanned 57 times this season. Barring trade or injury he will not see any sort of consistent playing time for the Red Sox at the big-league level. And even if he does, either in Boston or somewhere else, it remains to be seen whether he would be anything more than a Daric Barton clone.
3. Tony Sanchez, C, PIT - Sanchez missed a golden opportunity this season to seize control of the catching duties for the Pirates. The Bucs have been racked by injuries and are on their fifth and six backstops of the season, respectively. However, Sanchez has struggled in 2011. Arguably the best hitting prospect in the Pittsburgh system, Sanchez got reprimanded by the team recently after tweeting about poor umpiring while playing at Double-A Altoona. Likewise, he hasn't been hitting much either. Over his last 10 games, Sanchez is batting .200/.250/.200 with no extra-base hits. His stats on the year are average, if unspectacular, as the 23-year-old is hitting .257/.356/.326 with two home runs, 21 RBI and four steals. He still has time to turn things around, but Sanchez could have really put pressure on ownership to make him the everyday catcher with a torrid start.
4. Brett Oberholtzer, P, ATL - Notoriously a pitcher who pounds the strike zone, Oberholtzer has paid for his transgressions this season with Double-A Mississippi. Over his last 10 starts, the 21-year-old lefty has posted a bloated 5.74 ERA. Over that span, opposing batters are hitting .301 against him. Likewise, he's allowed at least five runs in four of his last five starts. Oberholtzer has been uncharacteristically wild over those last five outings, walking 13 batters total. By comparison, he walked 23 batters in 135.2 innings last season. The 6-2, 230-pounder must adjust to hitters at the higher levels, as he's not fooling them at this juncture.
5. Jay Austin, OF, HOU - Austin has battled strikeout concerns, fanning 61 times in 62 games for High-A Lancaster. He has also been caught stealing 10 times in 25 attempts, not great numbers for an alleged speedster. His line of .251/.317/.373 will not blow anybody away either. Though he is on pace to tally a career high in walks, Austin has never hit more than .267, and has never posted an OBP higher than .320. Though he is just 20, Austin has a lot of work to do if he is to become a prototypical leadoff hitter.
6. Jonathan Singleton, 1B, PHI - Knowing full well that they have Ryan Howard entrenched at first for years to come, the Phils attempted to move Singleton to the outfield at High-A Clearwater after a breakout 2010 season with Low-A Lakewood. The 19-year-old didn't take well to the position change, though, and his hitting has suffered as well. Over his last 10 games, Singleton is batting just .147/.326/.206. He has struck out 60 times in 56 games this season. The 6-2, 215, left-handed hitter has smashed just three home runs and driven in a measly 21 runs over that span. Singleton has really struggled against lefties, batting just .148 against southpaws. He's been moved back to first, which will hopefully aid his swing as well as his confidence.
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